KZ750 primary chain

Am I right in assuming there is no tensioning mechanism? It rattles like fuck at idle, once it gets going it sounds fine but at idle it sounds terminal. They're not cheap to buy and I was wondering at what millage it would need replacing? Bike has done 31K miles

No primary chain tensioner on the air cooled fours, the later water cooled motors did. At 50k plus they get a bit sloppy. Measurement of wear is quite a rough test and not too accurate.

Clutch basket rattle can be improved with a carb balance and tune.

My test for a motor is put a rag over the exhaust and rev it, it should whirr like an electric motor.

The big suzukis and kz900 series used used a gear driven primary,

The chain shouldn't be worn out in 31k. 131k then maybe.

I think the ZR-7 has a tensioner on the primary chain.

Oh, and slop in the clutch hub is epidemic on the 650/750 bikes because the cush drive rubbers shrink. There are a couple of options of nice aftermarket rubber cushions that will tighten up the hub appreciably. A very worthwhile improvement and highly recommended in my opinion.

Sync the carbs after the valves are adjusted and it should go away.
Steve

swest wrote: Sync the carbs after the valves are adjusted and it should go away.
Steve

^This. When I got my 750 it sounded like a rock tumbler at idle. Adjusted valves and synchronized the carbs, almost no noise now. It also helps to set idle speed a little higher. I keep mine at 1200.

Great info guys, thanks